Automatic antenna regulation



April 26,1927.

W. W. BROWN AUTOMATIC ANTENNA REGULATION Filed Dec. 2 1925 lnvenborz William W Brown, y ,J

His Attorney.

Pee-tea er; 12s, 1927. STAT ES PATENT o Y wrnrmm'w..nnown, or SCHENECTADY, NEW roan, ASSIGNOB To seminar. Emma FFlE.

COMPANY, A CORPORATION OF NEW YORK.

AuTomATIo ANTENNA uncommon.

Application filed December 29, 1925. Serial No. 78,201.

My present invention relates to improveinents, in meansfor regulating the resonant 3 1. wave length of an antenna system.

It is an object of myinvention to )rovide means whereby the desired relation etween capacityv and inductive reactances may be automatically maintained In carrying my invention into effect, I

' employ a phase relay having a rotary armature providedw'ith two differentially related windings spaced 90 apart and supplied fro-ma: substantially constant source of alternating current. Cooperatingwith these windings :is a stationaryfield-member having a winding connected in series relation with the antenna. If the antenna 1s exactly in tunewith the electromotive force supplie'd "fromthe constant source, no rotation of the phase relay armature will occur. If, however, any change. occurs ili'tlie capacity of the antenna, the phase relation of the antenna current and the armature currents will change, with; the result that the armature-wil-l rotate either in a forward or in i a reverse directiom. This rotation is taken advantage of to icon'trol switching means whereby the inductive reacta'nce of the 'an tenna circuit maybe altered to restore the tuning of the antenna to normal.

. The .novelfeatureswhich I believe to be characteristic of my invention are set forth witli'particularity in the appended claims. My invention, itself, however, both as to its organization and method of operation will best be understood by reference to the followin specification taken in connection with t 1e accompanying drawing in which the single. figure shows diagrammatically a circuit or an-ization whereby my invention may becarried into eileot. I Referring to the drawing, I have indicated at 1, a well known type of high frcfield member 3 the latter being driven by a constant speed motor 4. 1 Certain of the armature windings are connected to the prima'ry winding 0 a transformer 5, the secondary winding of which is connected in series with an antenna 6. Included in circuit with theant'enna 6 is a manually adjustable tuning coil 7 by means of which initial adjustment ot' the antenna impedance may be i i made, amotor operated variometer 8, and

the field winding 9 of a phase relay 10.

Winding 9 is mounted on a coremeinber 11 composed of thin enameled iron strips and is connected to ground as indicated at 12.

The armature member 13 of the phase relay'is energized from one of the armature coils '2 of the high frequency alternator l. Included in circuit with the latter armature coil is a circuit including two branches, one of which includes a capacity unit 14, an adjustable resistance unitlh andan arma-,. ture windin 16, while the other branch in? eludes an ac justable inductance unit 17. and an armature winding 18.. Armature windings 16 and 18 are spaced apart on the core of armature 13. With the connection branch may be displaced approximatel in phase from that in the other branc 1.

Mounted on the armature shaft 19 of the phase relay-is conducting disk 20 which may e made of copper, aluminum, or other conducting material, and a switch arm 21 adapt ed to cooperate with a pair of contacts 22 and 23 to selectively control the cnergization of a pair of directional relays 24; and 25. Cooperating with the disk 20 is a dampmg magnet v20'. Switch arm 21 is provided at one end with a soft iron armature 26 which cooperates with a magnet 27 whereby arm-21 may be held in central position.

Energization of relay Qlcloses a circuit I in one direction. Energization of relay 25 closes a circuit to the armature and field windings of motor 34 through contactors.,'31 and 38 and cooperating contacts 89 and 40. While the direction of the current supplied to the field winding 35 is not changed by energization of relay. 25 it will be noted that the direction of the current supplied tothe armature 33 of the motor is reversed, with the result that the direction otrotation of motor 35 is reversed. Deenergization of the reversing switches 24 and 25' closes a dynamic braking circuit for the motor armature through contactors 29 and 31 and cooperating contacts 32 and 41, so that overroo iii

ru'nningof' the variometer motor is prevented. I 7

When the. antenna is employed for telegraphy, the phase relay has a tendencyt tpllow the. telegraph signals, and unless the signaling key is held down forarelatively long period of time the directional relays 2a and 25 will not remain energized long enough to cause thevariometer 34 to operate through the required range. In order to ovecome this defect, I have provided a time delay relay e2 comprising acoil 43, and a contactor 4A which cooperates with contacts 45. A dashpot 46 isconnected to contactor 4.4 so as to retard movement thereof inan upward directiornl Vhen arm 21 engages contact 23,- relay 24a" taining circuit. If the engagement-of arm 21 with contact 23 is of very short, or. inon'ientar-y duration, the dccnergization oi the operating coil of relay 2lwill be controlled by the time delay relay l2, otherwise the deenergization of the relay 24: will be caused by the separation of arm 21 and contact 23.

In the operation or" my device as long as the antenna and the high frequency electromotive force generated by machine 1 are in tune, the current supplied to the field wind ing 9 will be in quadrature with the currents supplied to windings 16 and 18 of the phase relay 10 so that no movement of armature 13 will takeplace. If, however, the capacity of the antenna changes from any cause, the phase relation of the currents in windings 9, 16' and 18 will change so that rotation of the phase motor or relay 10 will take place in one-direction or the other, depending on the nature of the corerction to be made to the antenna. If the capacity of the antenna has decreased the phase relay will rotate in a di rection to energize, for example, relay 24 to close a circuit from the source 0t current a supply 28 to the variometer motor 34 which will cause rotation of, the variometer to increase the inductance of the antenna circuit. Likewise, when the capacity of the antenna has increased from any cause, phase relay 10 will rotate in the opposite direction and cause energization of relay to cause operation of the variometer 34; in the opposite direction to decrease the inductance of the antenna circuit. I

' By the use of a phase relay having a pair of differentially related armature windin s cooperating with a third winding I obtain a relay which is particularly sensitive to changes in antenna capacity. The ese of the, I 1 dampin magnet 20 in connection with the phase re ay makes the operation of the relay deadbeat, and ositive in character.

v I have foun thatthe employment of the time delay relay 42 is especially desirable and necessary where the antenna is used for telegraphy, if proper correction is to be made in the antenna circuit forchanges in the antenna Wave length. While I have shown the variometer as mounted on the same sha'lt as the motor armature '33, ob-

viously this connection maybe made through gearing or in any suitable manner desired.

By the provision of a dynamic braking for constant frequency, but dill'ering in phase, to

said armature windings, and means for supplying to said field winding acurrent havinga phase relation to the other currents which varies with variations in the capacity of the antenna.

2. In combination, an antenna, means including a relay for maintaining the tuning of the antenna substantially constant, said rc-, lay including a field Winding and an arm-a ture cooperating therewith, said armature having a plurality of windings, means for supplying currents having a substantially constant frequency, but ditl'ering in phase, to said armature windings, means for supplying to said field winding va current have i-ng a phase relation to the other currents which varies with variations in the capacity of the antenna, and damping means cooperating with said armature.

, 3. In combination, an antenna, a source or" high frequency electromotive force connected therewith, an electromagnetically operable, variable impedance for controlling thetuning of the antenna, a relay including a coil in the circuit of said antenna and a pair of coils supplied with currents havin aisubstantially constant frequency but di fering in phase, and means controlled by said relay for controlling the adjustment of said variable impedance.

4. .In combination, an antenna, means whereby high frequency electromotive force may be supplied to said antenna, means including a relay for maintaining the tumn of the antenna substantially constant, sai relay comprising a motor having a pair of differentially related armature windings and a field win ing cooperating therewith, said differentially related windings being supplied from a source of energy having a substantially constant frequency, and said field winding being energized by a current the phase relation of whichwith respect to the armature current varies with the capacity of the antenna. I

T). In combination, an antenna, means whereby high frequency eleetromotive force may besupplied to said antenna, means including a relay for maintaining the tuning of the antenna substantially constant, said a field win ing cooperatin winding being energized i phase relation of which with respect to the y current the armature currents varies with variations in the capacity of the antenna, and magnetic damping means cooperating with said motor. 6. In combination, an antenna, a source of high frequency electromotive force connected thereto, means including a relay for maintaining .the tuning of said antenna substantially constant, said relay comprising an armature and a cooperating field winding, said armature having two windings spaced apart substantially 90, means for supplying currents differing in phase to each otraid armature windings from a source of energy having a substantially constant frequency, and meansiior supplying to said field winding :1, current having a phase relation to the armature current which varies with variations in the impedance of the antenna.

7. In combination, an antenna, motor operated means'i'or maintaining the tuning of said antenna substantially constant, switching means for controlling the direction of operation of said motor operated means, a plurality of coils "for operating said switching means, means for selectively energizing said coils in accordance with variations in the impedance of the antenna and means for maintaining the energization of said coils for a predetermined period of time indeprudently of said selective means.

S. in combination, an'ante'nna, means for maintaining the tuning of said antenna substantially constant, said means including an impedance unit and a motor, a plurality or magnetically operated switches for controlling the direction of operation of the motor, means for selectively energizing said switches in accordance with variations in the impedance of said antenna and a time delay switch for controlling the operation of said switches.

9. In combination, an antenna, means for maintaining the tunim of said antenna substantially constant said means including an impedance unit and a motor, a plurality. of magnetically operated switches for controlling'the direction of operation of'the motor, means for selectively energizing said switches in accordance with variations in the impedance of said antenna, and an electromagnetic time delay relay adapted under certain conditions to control cleanergization of said electromagnetically operated switches.

10. In combination, an antenna, a source of high frequency electromotive force connected thereto, means for maintaining the tuning of the antenna substantially constant,

said means including a motor, an impedanceunit operated thereby, means selectively energized in accordance with variations in the impedance of the antenna for operating said motor in either direction, and means for closing a dynamic braking circuit to said motor when said selectively energized means are 'deencrgized.

11. In combination, a reversible motor, a pair of magnetically operable reversing switches for controlling the direction of operation of a motor, electr'omagnetically operable means controlling the energization of the reversing switches, means for maintaining the electromagnetically operable means in a normally inoperative position, and means controlled by the motor for controllin the energization of said electromagneticai y operable means. i

12. In combination, a reversible motor, means for controlling the direction of operation of said motor, said means including a rotary motor, a switch arm operated by the rotary motor, and a pair of contacts cooperating with said switch arm to control the direction of operation Ofsflid reversible motor, magnetic means cooperating with said switch arm to normally hold said arm in an inoperative position, and means controlled by the reversible motor for controlling the energization of the rotary motor.

In witness whereof, I have hereunto set my hand this 24th day of December, 1925.

\VILLIAM W. BROWN. 

